叶栅参数对液力缓速器起效特性影响规律研究

The cascade parameters have a decisive influence on the steady-state braking characteristics of the hydrodynamic retarder, but their influence on the dynamic braking characteristics, especially the onset characteristics of the hydrodynamic retarder to ensure the rapid braking response, is rarely involved. In order to improve the onset characteristics of the hydrodynamic retarder and ensure driving safety, the dynamic characteristics prediction model of the hydrodynamic retarder brake is constructed when the load inertia and charging mode are given. The angular velocity and angular acceleration of the moving wheel are predicted by integrating the distribution of the blade surface pressure, and the trend of the braking torque and rotation speed over time in the onset process is obtained, which is compared and verified by the bench test. Given the typical parameter configurations of the main cascades and auxiliary cascades with different moving and fixed wheels, the influence of the cascade system parameters on the onset characteristics and the changes in the internal flow state of the wheel cavity is analyzed. The results show that the main cascade parameters of the moving and fixed wheels affect the derivation and development of the vortex structure of the oil flow inside the wheel cavity, and the onset characteristics reflect the difference between the peak torque and the onset time. The prediction method in this paper can provide a theoretical basis for the optimal design of the dynamic characteristics of the hydrodynamic retarder.